This invention relates to an electrical power steering system.
In an electrical power steering system, the angle of displacement of a first shaft connected to a steering wheel with respect to a second shaft mechanically coupled to wheels to be steered is detected, and a servomotor or the like rotates the second shaft according to the angle of displacement thus detected. In general, the first and second shafts are arranged in one line, and a displacement angle detector is disposed between the two shafts. Since the displacement angle detector operates to detect the angles of relative rotation of the two shafts, it is absolutely necessary to provide lead wires for the detector in order to forward the detection signal to the control circuit of the servomotor. The detector is fixedly mounted on the first shaft and/or the second shaft. Since the displacement angle detector makes a circular motion as the shaft is turned, the lead wires must be sufficiently long, and it is essential that the lead wires are arranged so that they may not obstruct the rotation of the shaft.